I have an avi video with video codec mp4v and PCM audio. When I bring the video into Vegas Pro, it loads up fine except the audio gets seriously messed up. It gets chopped. See the waveforms below.

I used ffmpeg to extract the audio using the command ffmpeg -i video.avi -vn -acodec copy audio.wav. The resultant file will load correctly in Vegas Pro. See the waveforms and compare. These should look exactly the same.

Good and Bad Waveforms

What is causing this and how do I fix it?

ffprobe reports the following on the file:

Input #0, avi, from '01-1.avi':
  Duration: 02:01:44.47, start: 0.000000, bitrate: 2060 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (MP4V / 0x5634504D), yuv420p, 1024x768 [SAR 1:1 DAR 4:3], 626 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
      title           : DVI2USB 3.0 [D2S354466]
    Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, 2 channels, s16, 1411 kb/s
  • Mux to another AVI or MOV and check. Could be something as simple as a buggy or non-standard AVI muxer used by the original app. I notice that the audio is 2ch but the waveform is 1ch. Is that a compare of 1 of the channels or is the stream selection set to 'combined'?
    – Gyan
    Jan 24, 2017 at 9:48
  • @Mulvya Yes, two channels in the file, but I set vegas to only show the one that's there. The other channel is blank. No feed when recorded, apparently.
    – user3643
    Jan 24, 2017 at 9:53
  • @Mulvya So ffmpeg -i input.avi -vcodec copy -acodec copy output.avi? Is that what you want me to try? Just tried it, didn't work.
    – user3643
    Jan 24, 2017 at 10:11
  • And also to MOV.
    – Gyan
    Jan 24, 2017 at 10:34
  • @Mulvya Thank's for the suggestion. I ran this command: ffmpeg -i input.avi -vcodec copy -acodec copy output.mov. The mov file will open the audio correctly. The video will not load, however. Seems like progress. What does this mean, though? An issue with Vegas and AVI files?
    – user3643
    Jan 24, 2017 at 16:41

1 Answer 1


I've been able to solve the issue recently with the following command in ffmpeg:

ffmpeg -i "input.avi" -c copy "output.mov"

I still have no understanding why Vegas would not work with the AVI. My system does this container rewrap at about 350x, so it's very fast. The only issue is if you have a ton of videos and you create a batch file, you should check your hard drive space before you try it.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.